BEIJING, April 19 (Xinhua) -- China cut the number of its economic development zones from 6,866 in 2003 to 1,568 at the end of last year, said sources with the National Development and Reform Commission (NDRC) on Thursday. The total area of the country's economic development zones has shrunk from 38,600 square kilometers to 9,949 square kilometers. An NDRC official said "the State Council prohibits the building of new economic development zones and expanding the existing ones". Over the past four years, the NDRC have integrated adjacent economic development zones in counties and cities, leaving only one in every county or in the outer suburbs of each city. Economic development zones have been removed from environmentally sensitive areas, such as water source protection areas, nature reserves, scenic spots, forest parks and wetlands. Restrictions have been imposed on building chemical, paper making and pharmaceutical plants upstream or upwind of residential areas. China began to cut back on its economic development zones in July 2003 because they were eating up too much arable land and damaging farmers' interests.